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Hand held phase sense antennas with visual and audible response

The Vector-Finder Series of VHF direction finding antennas provide a compact, lightweight, active antenna, suitable for use in the field with handheld transceivers and scanning radios. The mechanical design allows the sense antennas to be folded back to provide a compact unit, easily stowed or transported in any vehicle. The system interfaces with any FM receiver or transceiver via the antenna jack and the earphone jack. Several different models are available to suit your pocketbook or unique field application, all of which operate on the phase shift technique. The VF-142Q models incorporate left-right indicators as well as an audible response from which the user can determine the true direction of the radio signal. The other types utilize the audible response generated by the equipment and heard on the userís receiver or transceiver. All models operate from a 9-volt battery.


NEW! The Vector-Finder VF-145 L/LM Hand Held Direction Finding Antenna

National RF is pleased to announce a new and improved version of the Vector-Finder series of VHF radio direction finding equipment. Designated the VF-145 L and LM models, the equipment is similar in function to the existing VF-142 series of Vector-Finders. However, the new equipment incorporates a LED bar graph display in lieu of separate left/right LED's, as is used on the existing VF-142 series. The LED segments of the bar graph display provide an indication of the angle of the incoming radio signal over a 90 degree sector, this providing a more "user friendly" display system. The electrical and mechanical parameters and specifications of the new hardware are exactly the same as the VF-142 series. 


Mechanical Dimensions, All Models

Enclosure Overall Height, including pistol-grip and compass:

11 3/4 inches
Front to Back Depth: 7 1/2 inches
Width with Antennas Flush against the enclosure: 3 1/2 inches
Antenna Vertical Length (fully extended)  38 inches
Dimensions Between Sense Antennas (arms opened)  18 inches
Direction Indication Method, All Models Front Panel mounted LED diodes indicating Left, Right, and Center directions of incoming radio waves.  VF-145 L/LM utilize a 10 segment LED array, indicating an approximate 90 degree arc segment in the direction pointed.  

Audible adjustable tone available via speaker  mounted inside antenna enclosure or from front panel earphone jack.

Compass and Resolution Type: Ritchie Navigation oil filled floating indicator magnetic compass with luber's line.
Incremental Compass Calibration: Every 5 degrees
LOS Compass Resolution:   Approx. 2 degrees
Electronic resolution of LOS: Better than 2 degrees
Antenna and Interface Specifications, All Models 2 Collapsible Dipole Antennas configured in a phase sensing array with vertical polarization 50 Ohm coaxial feedline with BNC connector and 1/8 inch mono plug for interface to radio earphone output.
Power Requirements:   Single 9-volt Alkaline battery, approx. 30 ma current draw when activated.  Activation by push button switch mounted on pistol grip handle.


Type VF-142Q FREQ. RANGE; 144-230 MHz.
Audible and LED left-right direction indication Price $239.95


Type VF-156Q FREQ. RANGE; 156-163 MHz.
Marine band. Audible and LED left-right direction indication Price $259.95


Type VF-142QM FREQ. RANGE; 144-500 MHz.
Audible and LED left-right direction indication Price $289.95


The VF-145L FREQ. RANGE; 130 MHz to 300 MHz Price $279.95


  The VF-145LM FREQ. RANGE; 130 MHz to over 500 MHz. Price$329.95.


Shipping/handling, all models, $7.00. California Residents must add Sales tax.

Overseas Customers: Please note that an additional overseas shipping charge will be applied to your order. National RF will notify you of the exact amount of shipping to your country via e-mail, after your e-order is placed. The customer is responsible for all and any customs or tarrif charges applied to your order.


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